Tag Archives: 10 Gigabit Ethernet

Since the establishment of 10 Gigabit Ethernet, it has been employed by large amount of enterprises in their corporate backbones, data centres, and server farms to support high-bandwidth applications. But how to achieve a reliable, stable and cost-effective 10Gbps network? There are ten things you should know before doing the deployment.

More Efficient for the Server Edge

Many organizations try to optimize their data centres by seeking server virtualization which supports several applications and operating systems on a single server by defining multiple virtual machines on the server. Because of this, the organizations can reduce server inventory, better utilize servers, and mange resources more efficiently. Server virtualization relies heavily on networking and storage. Virtual machines require lot of storage. The network connectivity between servers and storage must be fast enough to avoid bottlenecks. And 10GbE can provide the fast connectivity for virtualized environments.

More Cost-effective for SAN

There are three types of storage in a network: direct-attached storage, network attached storage, and SAN. Among them, SAN is the most flexible and scalable solution for data centre and high-density applications. But it costs much and needs special trainees for installing and maintaining the Fibre Channel interconnect fabric.

The internet small computer system interface (iSCSI) makes 10 Gigabit Ethernet an attractive interconnect fabric for SAN applications. iSCSI allows 10 Gigabit Ethernet infrastructure to be used as a SAN fabric which is more favorable compared with Fibre Channel. Because it can reduce equipment and management costs, enhance server management, improve disaster recovery and deliver excellent performance.

Reducing Bottlenecks for the Aggregation Layer

Today, traffic at the edge of the network has increased dramatically. Gigabit Ethernet to the desktop has become more popular since it becomes less expensive. More people adopt Gigabit Ethernet to the desktop, which increases the oversubscription ratios of the rest of the network. And that brings the bottleneck between large amounts of Gigabit traffic at the edge of the network and the aggregation layer or core.

To realize 10 Gigabit Ethernet network deployment, three important factors should be considered, including the type of fibre cable (MMF of MF), the type of 10 Gigabit Ethernet physical interface and optics module (XENPAK, X2, XFP and SFP+).

Form factor options are interoperable when 10 Gigabit Ethernet physical interface type is the same on both ends of the fibre link. For example, 10GBASE-SR XFP on the left can be linked with one 10GBASE-SR SFP+ on the right. But 10GBASE-SR SFP+ can’t connect to one 10GBASE-LRM SFP+ at the other end of the link.

Copper Cabling Solutions

As copper cabling standards becomes mature, the copper cabling solutions for 10GbE is becoming common. Copper cabling is suitable for short distance connection. The are three different copper cabling solutions for 10 Gigabit Ethernet: 10GBASE-CX4, SFP+ DAC (direct attach cable) and 10GBASE-T.

10GBASE-CX4 is the first 10 Gigabit Ethernet standard. It’s economical and allowed for very low latency. But it’s a too large form factor for high density port counts in aggregation switches.

10G SFP+ DAC is a new copper solution for 10 Gigabit Ethernet. It has become the main choice for servers and storage devices in a rack because of its low latency, small connector and reasonable cost. It’s the best choice for short 10 Gigabit Ethernet network connection.

10GBASE-T runs 10G Ethernet over Cat6a and Cat7 up to 100 m. But this standard is not very popular since it needs technology improvements to reduce its cost, power consumption, and latency.

For Top of Rack Applications

A top-of-rack (ToR) switch is a switch with a low number of ports that sits at the very top or in the middle of a 19’’ telco rack in data centres. A ToR switch provides a simple, low-cost way to easily add more capacity to a network. It connects several servers and other network components such as storage together in a single rack.

ToR switch uses SFP+ to provide 10G network in an efficient 1U form factor. DAC makes rack cabling and termination easier. Each server and network storage device can be directly connected to the ToR switch, eliminating the need for intermediate patch panels. DAC is flexible for vertical cabling management within the rack architecture. And the cabling outside the rack, the ToR switch uplink connection to the aggregation layer, simplifies moving racks.

The following figure shows a 10 Gigabit Ethernet ToR switching solution for servers and network storage. Because the servers are virtualized, so the active-active server team can be distributed across two stacked witches. This can ensure physical redundancy for the servers while connected to the same logical switch. What’s more, failover protection can be offered if one physical link goes down.

Conclusion

10 Gigabit Ethernet network is not the fastest but quite enough for common use in our daily life. So you should better read this article before you do the deployment. Besides, FS.COM provides both fibre and copper cabling solutions for 10G network. For more details, please visit www.fs.com.

10 Gigabit Ethernet has been applied for a long time in data centers and enterprise LANs. For 10G Ethernet connection, there are both single mode and multimode solutions. This post will introduce 10GBASE-LRM – a new 10G multimode optical solution.

First let’s see the original multimode solutions and supportable distances for 10G Ethernet.

10GBASE-S operates at 850nm wavelength. It can support up to 300m distance over laser-optimised OM3. This makes it a popular standard for data centers and cooperate backbones. For the conventional OM1 and OM2 which are not optimised for laser transmission, the furthest supportable distance is 33 m and 82 m. So these two solutions are only used in equipment rooms or small data centers.

10GBASE-LX4 was specified to support 300 m over three cable types. So it relies on coarse wavelength division multiplexing (CWDM) which is more complex and expensive technology. 10GBASE-LX4 operates at 1300nm wavelength and that requires additional cost on mode-conditioning patch cords (MCPCs).

The high cost and relatively slow adoption of 10GBASE-LX4 drive the development of a new standard—10GBASE-LRM. 10GBASE-LRM is developed to offer a longer reach for conventional fibre cables at a lower cost and smaller size than 10GBASE-LX4. The following will talk about 10GBASE-LRM from three sides.

10GBASE-LRM Transmission Distance

On condition the supporting distance, 10GBASE-LRM can only support 220 m. It’s suitable for LAN networks within buildings. But a cabling survey provides that for 10G network, the distance is not able to address 30% of in-building channels.

10GBASE-LRM Electronic Dispersion Compensation

The key to the long reach of 10GBASE-LRM on conventional multimode fibre is electronic dispersion compensation (EDC). EDC is deployed as an integrated circuit that acts like a complex filter on the received signal from the optical fibre. The purpose is to extend the maximum supportable distance. 10GBASE-LRM applies EDC technology and is therefore independent of the optical wavelength. 10GBASE-LRM operates at 1300 nm.

EDC chips is added to a linear detector in the receiver. As an additional component, it increases cost, consumes power and wastes heat. It can only work as intended in conjunction with a linear detector and amplifier. Because the EDC device must operate on a faithful analog rendition of the optical waveform in the fibre. For 10GBASE-LRM, to reproduce the optical waveform with precision, extra requirements and cost on the receiver design are needed.

10GBASE-LRM Multiple Transmit Launch Conditions

In order to improve the chances of operating at a higher bandwidth, 10GBASE-LRM relies on multiple transmit launch conditions.

One launch is achieved by using mode-conditioning patch cord. The other launch is produced using a regular multimode patch cord. Through the two launches, different modes can be achieved and a favorable operating condition can be easily found.

There are four possible patch cord combinations at both ends of the channel. The preferred launch uses MCPCs on both ends. This process requires a test for link stability for each configuration. The user should shake and bend the patch cord at the transmit end while observing channel health indicators at the receive end. The shaking and bending of the cords causes changes to the received waveform which the receiver must tolerate in normal operation. If there were transmission errors, then users should change another launch. The errors indicate that the channel is operating near or beyond the limit of the receiver’s capability and the link may fail in operation.

However, the 10GBASE-LRM standard’s committee refuse to implement this channel test. So the burden of the shaking and bending lies on the users. It’s not good for the popularity of 10GBASE-LRM.

Comparison of Several 10G Transceivers Cost

The following will compare the cost of 10G transceivers from several sides, including laser, receiver, package and cords.

Through the comparison among these 10G optical transceivers, you may find which one costs fewer. 10GBASE-LRM transceiver is cheaper than 10GBASE-LX4, more expensive than 10GBASE-L and 10GBASE-S transceivers.

Conclusion

10GBASE-LRM is a multimode solution for 10 Gigabit Ethernet. Based on the above content, 10GBASE-LRM has some advantages over 10GBASE-LX4. It offers lower cost and smaller package. But the distance and reliability are not very ideal. Compared with 10GBASE-S, 10GBASE-LRM is not so good as to the cost, simplicity, reliability and distance capability. FS.COM provides various types of cost-effective 10GBASE transceivers, such as 10GBASE-LR, 10GBASE-SR, 10GBASE-ER, etc. Other compatible brands like Cisco, Juniper, Arista, Brocade are also available. Among so many choices, you must choose the most suitable solution for your network connection.

The demand for high bandwidth promotes the development of data transmission technology. Ethernet standard continuously evolves to meet fast speed need, from 100BASE, 1000BASE to 10 Gigabit Ethernet. Meanwhile, the data carrying technology also develops to provide great bandwidth for transporting data with low cost, such as the copper and fibre cable as well as optical transceiver module.

Figure1. 10 Gigabit Ethernet Cabling

Media for 10 Gigabit Ethernet: Copper and Fibre

In 10 Gigabit Ethernet, copper and fibre are used to transport data. Each one has its own advantages and disadvantages.

Copper is more affordable and easy to install. It acts the best when used in short lengths, typically 100 meters or less. But when deployed over long distance, electromagnetic signal characteristics will influence its performance. Besides, bundling copper cabling can cause interference, which makes it difficult to employ as a comprehensive backbone. So copper cabling are widely used in PCs and LANs communication network instead of campus or long-distance transmission.

Compared with copper, fibre cabling is usually used for long distance communication among campus, and environments that need protection from interference, such as manufacturing areas. In addition, fibre cabling is more reliable and less susceptible to attenuation, which makes it suitable for data transmission distance over 100 meters. But fibre still has drawbacks. It’s more costly than copper.

The Evolution of 10 Gigabit Ethernet Cabling

Since 10 GbE technologies have changed, so have the cabling technologies. There are two main standards: IEEE802.3ae and IEEE802.3ak. Factors covered in these standards like transmission distance and equipment being used are helpful to determine the cabling strategy.

IEEE802.3ae

IEEE802.3ae standard updates the existing IEEE802.3 standard for 10GbE fibre transmission. The new standard defines several new media types for LAN, metropolitan area network (MAN) and wide area network (WAN) connectivity.

10GBASE-SR – it supports 10GbE transmission over standard multimode fibre (850 nm) for distances of 33 and 86 meters. The SR standard also supports up to 300 meters using the new 2000MHz/km multimode fibre (laser optimized). This one is the lowest-cost optics for 10GbE.

10GBASE-LX4 – it can support multimode fibre for distances up to 300 meters using Coarse Wavelength Division Multiplexing (CWDM). The LX4 standard also supports single mode fibre for up to 10 Km. LX4 is more expensive than both SR and LR because it requires four times the optical and electrical circuitry in addition to optical multiplexers.

10GBASE-ER – it uses optics (1550nm) to support single mode fibre up to 30 km.

IEEE802.3ak / 10GBASE-T

10GBASE-T is the latest proposed 10GbE standard for use with unshielded twisted-pair (UTP) style cabling. This standard is to improve the performance and increase the transmission distance at a lower cost. Category 5 (Cat 5) and Category 6 (Cat 6) are the most common cabling systems being installed today. But Cat 5 can’t meet the bandwidth demands of 10GbE’s transmission. To meet the needs of 10GbE, manufacturers create Category 6A (Cat 6A), designed with existing Cat 6 cable but measured and specified to higher frequencies. In addition to Cat 6A, 10GBASE-T will operate on Category 7 (Cat 7) cables.

10GbE Transceivers

Except the cabling, transceivers also need to be considered for the network connectivity. Transceivers provide the interface between the equipment sending and receiving data. 10GbE has four defined transceiver types, including XENPAK, X2, XFP and SFP+ (Small Form-factor Pluggable Plus). These transceivers are pluggable and are compliant with 802.3ae standard.

Among them, SFP+ is the smallest 10G form factor. And it can interoperate with XENPAK, X2, XFP interface on the same link. Fiberstore provides a number of interfaces attempted to satisfy different objectives including support for MMF and SMF compatibility, such as SFP-10G-SR, SFP-10G-LR, SFP-10G-ER, SFP-10G-ZR, etc. For example, SFP-10G-SR transceiver module can support 300 meters data transmission distance over 850 nm multimode fibre. And SFP-10G-LR module supports the link length up to 10 kilometers over 1310 nm single mode fibre.

Figure2. 10 Gigabit Ethernet Transceiver

As the corresponding cabling technology gets great improvement, 10 Gigabit Ethernet is becoming more affordable and pervasive. 10G network brings us higher speed. For 10G network connectivity, SFP+ transceivers are recommended to transport data over copper or fibre cabling.

Nowadays, billions of file cabinets and mountains of papers stored in computers need to be transmitted at high speed with great efficiency. Computer networking technologies are key to meet this demand, allowing computers on the internet to send and receive information easily. This article will introduce the network technology: Ethernet which is widely used nowadays.

Ethernet is a family of computer networking technologies for local area networks (LANs) and metropolitan area networks (MANs), connecting more than 85 percent of the world’s LAN connected PCs and workstations. It is a link layer protocol in the TCP/IP stack, describing how networked devices transmit data on the same network segment and how to put data out on the network connection. Ethernet was commercially released in 1980 and first standardized in 1983 as IEEE 802.3. Its standards have been updated to embrace new media, higher transmission speeds and changes in frame content such as the new standard 802.3af defining Power Over Ethernet [POE] crucial to most Wi-Fi and IP telephony deployments.

Ethernet was initially designed to run over coaxial cables but has been updated to used for twisted pair cables and fibre optical fibres over years. The most commonly installed Ethernet systems are called 100 BASE-T (the “BASE-T” part means the systems use twisted-pair cabling) which provides transmission speeds up to 100Mbps. It is typically used for LAN backbone systems, supporting workstations with 10BASE-T cards. Another widely used one is Gigabit Ethernet which is primarily carried on optical fibre with very short distances possible on copper media. It provides an even higher level of backbone support at 1000 Mbps or 1 Gbps. With the increasing of data transfer rates, the standards: 10 Gigabit Ethernet and 100 Gigabit Ethernet are available. Their data rates reached up to 10 gigabits per second and even 100 gigabits per second respectively, making them be good solutions to deliver high bandwidth in LANs.

100GBASE-LR4 CFP2 Optical Transceiver Module

It is concluded that Ethernet has evolved to provide excellent performance and network intelligence. As Ethernet data transfer rates are excepted to be increased to 400 Gbit/s by early 2017, Ethernet will be the most potential network technology in the future for its high-speed data transmission.

Fiberstore offers a wide range of products for 10GbE or 100 GbE applications such as the new product: 100GBASE-LR4 CFP2 Optical Transceiver module. The optical transceiver offers smaller size and lower power consumption for data centre networking, enterprise core aggregation, and service provider transport applications. For more information, please visit www.fs.com.